Ion channels and ion pumps are cell-membrane proteins that control the transport of positively or negatively charged ions (e.g., sodium, potassium and chloride) across the cell membrane. Ion channels play an important part of various animal and human functions including signaling and metabolism. Ion-channel dysfunctions are associated with a wide variety of illnesses. For instance, diseases resulting from ion-channel dysfunctions in the central nervous system include anxiety, depression, epilepsy, insomnia, memory problems and chronic pain. Other diseases resulting from ion-channel dysfunctions include cardiac arrhythmia, and type II diabetes. Researchers are continually discovering diseases associated with ion-channel functionality.
Several drugs have been discovered to modify ion-channel functionality; however, the number of clinically approved drugs for restoring ion-channel functionality is limited. A major bottleneck in the discovery and development of new ion-channel drugs lies in the technical challenge of quickly, efficiently and cheaply screening drug candidates to identify structures that affect ion-channel functionality. Common screening techniques use patch clamping to measure the voltage and/or current in a cell. Micropipettes affixed to the cell membrane obtain the measurement. For example, whole-cell configuration can be used to monitor the functionality of the ion channels throughout the cell. In this manner, changes in voltage or current due to an introduced drug can be monitored. Such methods require contact between the micropipette and the cell. For this and other reasons, such techniques leave room for improvement in their ability to screen drugs quickly, efficiently and cheaply.
These and other issues have presented challenges to screening of drug candidates, including those affecting ion-channel function.
While the invention is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.